In Game of Thrones/ASOIAF characters are reported dead or disappeared and later reappear or are replaced with pretenders. Was this a reality in medieval times (especially during political instability)? How did they prove their identity when they reappeared?

by Rec0nSl0th

[SPOILERS] Four of the Stark children were widely believed to be lost or "dead" (Sansa - disappeared from King's Landing and in hiding, Arya - believed to be dead but then replaced with an imposter, Bran and Rickon believed to have been killed) [/SPOILERS]

Does this parallel anything that happened in medieval times?

Broke22

There is a bunch of related answers in the FAQ.

https://www.reddit.com/r/AskHistorians/wiki/dailylife#wiki_proof_of_identity